1. Field of the Invention
This invention relates generally to the field of boatlifts for lifting watercrafts out of the water; and, more particularly to boatlifts that employ controlled power to accomplish the lifting and lowering functions. Still more particularly, the invention relates to a powered boatlift structure that incorporates a unique electronically controlled drive mechanism to effectuate the raising and lowering operation. Further, the invention relates to a boatlift structure having adjustable legs for leveling the structure, while being adapted for ease of mounting a covering canopy.
2. State of the Prior Art
The boating industry is ever-increasing in the number of people participating. The costs of boat ownership and maintenance are also increasing. Pleasure boats and their associated drive engines have tended to become heavier due to incorporation of additional features and accessories on the boats, as well as from additional user amenities, and due to general increases in the size of engines. Such weight increases have caused the prior art manually actuatable boatlifts to become marginal in user acceptability.
It has been recognized that it is desirable to provide lifts that allow boats to be lifted from the water for maintenance, repair, storage, or the like. Pleasure boat users have recognized the desirability of removing boats from the water when not in use, to allow surfaces to dry out and to prevent damage from wave action causing boat-impact with mooring structures. It has also been recognized that it is desirable to provide canopy protection to protect the boat surfaces and interiors from damages due to rain and deterioration from direct sunlight.
Over the years, boatlifts have been developed in various forms and configurations. Many prior art lifts include one or more cables coupled to lift or lower boat support structures. Prior art winch arrangements often involve a number of pulleys and cables, arranged as manually operable winches, to lift boats through application of mechanical force applied via manipulation of manually actuated rotatable drive wheels. Such manually operable winches do not readily accommodate or utilize the same amount of physical exertion for varying weight boats in that the mechanical advantages are usually fixed for each particular target load design. Further, such mechanical winches can be difficult to control when lowering boats into the water, and can cause injuries when inadvertently released.
Other prior art lift structures utilize hydraulic apparatus in various arrangements to lift and position boats. Such structures require availability of hydraulic fluid and availability of substantial power to drive the hydraulic apparatus. Hydraulic structures are relatively more complex and expensive to manufacture, maintain, and operate than other prior art manually operable mechanical winch structures.
Boatlifts are often positioned beside dock structures to provide ease of access. Such lifts are usually supported on legs that have foot structures to engage the support surfaces. Some leg structures are adjustable in length to accommodate variations in the levels of the supporting ground surfaces upon which the legs rest. Such adjustments allow the lifts to be leveled during installation, but many prior art level adjustment systems do not allow for ease of level selection nor are they readily adjustable after installation.
Some prior art adjustment systems have telescoping members that require pins to be inserted in mating holes in slidably engaged leg members to fix the particular height selections. Such mechanisms are difficult to adjust, and once installed are not readily subject to adjustment. Further, the incremental adjustments often do not allow the boatlift to be substantially leveled. To remedy the leveling problem, prior art lifts have required that shims or other props be utilized under the ground engaging feet to accomplish the final leveling process. These arrangements do not lend themselves to ready adjustment of the leveling of the lift at installation and do not allow ease of level adjustment that may be required as a result of one or more of the ground engaging feet settling.
Other prior art leg adjustment mechanisms involve threaded leg extension mechanisms that are activated from the top extremity of upright support member. Since canopy structures are often mounted to the tops of the upright support members, this form of height adjustment mechanisms makes it difficult or impossible to mount canopy structures on the support legs while maintaining the ability to further adjust leveling of the boatlift.
None of the prior art lift structures are adequate, nor are they designed to provide safety and flexibility in raising and lowering boats through use of a unique powered drive mechanism that allows smooth and linearly controlled raising and lowering with fingertip control. Prior art systems utilized in the pleasure boat industry have primarily been hand operated and have failed to show or utilize electronically controlled power to accomplish the safe raising and lowering functions. Further, the prior art lift structures do not provide convenient leveling mechanisms that allow close control and ease of adjustment of support leg positioning either by hand or with a power tool, while allowing a canopy to be affixed to the boatlift.